feat(admin): expose rebalance cleanup warnings

crates/cli/src/commands/admin/rebalance.rs

@@ -6,7 +6,7 @@ use serde::Serialize;
 use super::get_admin_client;
 use crate::exit_code::ExitCode;
 use crate::output::Formatter;
-use rc_core::admin::{AdminApi, RebalancePoolStatus, RebalanceStatus};
+use rc_core::admin::{AdminApi, RebalanceCleanupWarnings, RebalancePoolStatus, RebalanceStatus};
 
 /// Rebalance subcommands
 #[derive(Subcommand, Debug)]
@@ -217,6 +217,14 @@ fn print_rebalance_pool(pool: &RebalancePoolStatus, formatter: &Formatter) {
         formatter.println(&format!("    Last error: {error}"));
     }
 
+    if pool.cleanup_warnings.count > 0 {
+        formatter.println(&format!(
+            "    {} {}",
+            formatter.theme().warning.apply_to("Cleanup warnings:"),
+            format_cleanup_warnings(&pool.cleanup_warnings)
+        ));
+    }
+
     if let Some(progress) = &pool.progress {
         formatter.println(&format!(
             "    Progress:   {} moved, {} objects, {} versions",
@@ -242,6 +250,41 @@ fn print_rebalance_pool(pool: &RebalancePoolStatus, formatter: &Formatter) {
     }
 }
 
+fn format_cleanup_warnings(warnings: &RebalanceCleanupWarnings) -> String {
+    let mut details = vec![format!("{} warning(s)", warnings.count)];
+
+    if let Some(message) = warnings
+        .last_message
+        .as_deref()
+        .filter(|value| !value.is_empty())
+    {
+        details.push(format!("last message: {message}"));
+    }
+    if let Some(bucket) = warnings
+        .last_bucket
+        .as_deref()
+        .filter(|value| !value.is_empty())
+    {
+        details.push(format!("bucket: {bucket}"));
+    }
+    if let Some(object) = warnings
+        .last_object
+        .as_deref()
+        .filter(|value| !value.is_empty())
+    {
+        details.push(format!("object: {object}"));
+    }
+    if let Some(at) = warnings
+        .last_at
+        .as_deref()
+        .filter(|value| !value.is_empty())
+    {
+        details.push(format!("at: {at}"));
+    }
+
+    details.join(", ")
+}
+
 fn style_status(status: &str, formatter: &Formatter) -> String {
     match status {
         "Started" | "running" => formatter.style_name(status),
@@ -326,4 +369,20 @@ mod tests {
         assert_eq!(style_status("idle", &formatter), "idle");
         assert_eq!(style_status("Queued", &formatter), "Queued");
     }
+
+    #[test]
+    fn test_format_cleanup_warnings() {
+        let warnings = RebalanceCleanupWarnings {
+            count: 2,
+            last_message: Some("cleanup warning".to_string()),
+            last_bucket: Some("bucket-a".to_string()),
+            last_object: Some("object-a".to_string()),
+            last_at: Some("2026-06-12T00:00:00Z".to_string()),
+        };
+
+        assert_eq!(
+            format_cleanup_warnings(&warnings),
+            "2 warning(s), last message: cleanup warning, bucket: bucket-a, object: object-a, at: 2026-06-12T00:00:00Z"
+        );
+    }
 }

crates/cli/tests/admin_expand.rs

@@ -48,7 +48,7 @@ fn scale_start_dispatches_to_rebalance_start_with_expansion_json() {
 fn expand_status_dispatches_to_rebalance_status_json() {
     let config_dir = tempfile::tempdir().expect("create config dir");
     let (endpoint, receiver, handle) = start_admin_test_server(
-        r#"{"id":"rebalance-123","pools":[],"stoppedAt":"2026-05-06T00:00:00Z"}"#,
+        r#"{"id":"rebalance-123","pools":[{"id":0,"status":"Completed","used":0.5,"lastError":null,"cleanupWarnings":{"count":1,"lastMsg":"cleanup warning","lastBucket":"test-bucket","lastObject":"object-a","lastAt":"2026-06-12T00:00:00Z"},"progress":null}],"stoppedAt":"2026-05-06T00:00:00Z"}"#,
     );
 
     let output = Command::new(rc_binary())
@@ -73,7 +73,12 @@ fn expand_status_dispatches_to_rebalance_status_json() {
             .as_array()
             .expect("pools should be an array")
             .len(),
-        0
+        1
+    );
+    assert_eq!(payload["pools"][0]["cleanupWarnings"]["count"], 1);
+    assert_eq!(
+        payload["pools"][0]["cleanupWarnings"]["lastMsg"],
+        "cleanup warning"
     );
 
     let request = receiver

crates/cli/tests/admin_rebalance.rs

@@ -45,7 +45,7 @@ fn rebalance_start_dispatches_to_rebalance_start_json() {
 fn rebalance_status_dispatches_to_rebalance_status_json() {
     let config_dir = tempfile::tempdir().expect("create config dir");
     let (endpoint, receiver, handle) = start_admin_test_server(
-        r#"{"id":"rebalance-123","pools":[],"stoppedAt":"2026-05-07T00:00:00Z"}"#,
+        r#"{"id":"rebalance-123","pools":[{"id":0,"status":"Completed","used":0.5,"lastError":null,"cleanupWarnings":{"count":1,"lastMsg":"cleanup warning","lastBucket":"test-bucket","lastObject":"object-a","lastAt":"2026-06-12T00:00:00Z"},"progress":null}],"stoppedAt":"2026-05-07T00:00:00Z"}"#,
     );
 
     let output = Command::new(rc_binary())
@@ -65,7 +65,16 @@ fn rebalance_status_dispatches_to_rebalance_status_json() {
     let payload: serde_json::Value = serde_json::from_str(&stdout).expect("JSON output");
     assert_eq!(payload["id"], "rebalance-123");
     assert_eq!(payload["stoppedAt"], "2026-05-07T00:00:00Z");
-    assert_eq!(payload["pools"].as_array().expect("pools array").len(), 0);
+    assert_eq!(payload["pools"].as_array().expect("pools array").len(), 1);
+    assert_eq!(payload["pools"][0]["cleanupWarnings"]["count"], 1);
+    assert_eq!(
+        payload["pools"][0]["cleanupWarnings"]["lastMsg"],
+        "cleanup warning"
+    );
+    assert_eq!(
+        payload["pools"][0]["cleanupWarnings"]["lastBucket"],
+        "test-bucket"
+    );
 
     let request = receiver
         .recv_timeout(Duration::from_secs(5))

crates/core/src/admin/cluster.rs

@@ -730,11 +730,39 @@ pub struct RebalancePoolStatus {
     #[serde(default, rename = "lastError")]
     pub last_error: Option<String>,
 
+    /// Cleanup warnings observed after this pool finishes rebalance.
+    #[serde(default, rename = "cleanupWarnings")]
+    pub cleanup_warnings: RebalanceCleanupWarnings,
+
     /// Rebalance progress, if this pool is active.
     #[serde(default)]
     pub progress: Option<RebalancePoolProgress>,
 }
 
+/// Cleanup warnings recorded for a rebalanced pool.
+#[derive(Debug, Clone, Serialize, Deserialize, Default)]
+pub struct RebalanceCleanupWarnings {
+    /// Number of cleanup warnings observed.
+    #[serde(default)]
+    pub count: u64,
+
+    /// Last cleanup warning message.
+    #[serde(default, rename = "lastMsg")]
+    pub last_message: Option<String>,
+
+    /// Bucket associated with the last cleanup warning.
+    #[serde(default, rename = "lastBucket")]
+    pub last_bucket: Option<String>,
+
+    /// Object associated with the last cleanup warning.
+    #[serde(default, rename = "lastObject")]
+    pub last_object: Option<String>,
+
+    /// Timestamp of the last cleanup warning.
+    #[serde(default, rename = "lastAt")]
+    pub last_at: Option<String>,
+}
+
 /// Rebalance progress for a single pool.
 #[derive(Debug, Clone, Serialize, Deserialize, Default)]
 pub struct RebalancePoolProgress {
@@ -919,13 +947,18 @@ mod tests {
 
     #[test]
     fn test_rebalance_status_deserialization() {
-        let json = r#"{"id":"rebalance-1","pools":[{"id":0,"status":"Started","used":0.5,"lastError":null,"progress":{"objects":3,"versions":4,"bytes":1024,"remainingBuckets":2,"bucket":"bucket","object":"object","elapsed":10,"eta":20}}],"stoppedAt":null}"#;
+        let json = r#"{"id":"rebalance-1","pools":[{"id":0,"status":"Started","used":0.5,"lastError":null,"cleanupWarnings":{"count":1,"lastMsg":"cleanup warning","lastBucket":"bucket","lastObject":"object","lastAt":"2026-06-12T00:00:00Z"},"progress":{"objects":3,"versions":4,"bytes":1024,"remainingBuckets":2,"bucket":"bucket","object":"object","elapsed":10,"eta":20}}],"stoppedAt":null}"#;
 
         let status: RebalanceStatus = serde_json::from_str(json).unwrap();
 
         assert_eq!(status.id, "rebalance-1");
         assert_eq!(status.pools.len(), 1);
         assert_eq!(status.pools[0].used, 0.5);
+        assert_eq!(status.pools[0].cleanup_warnings.count, 1);
+        assert_eq!(
+            status.pools[0].cleanup_warnings.last_message.as_deref(),
+            Some("cleanup warning")
+        );
         let progress = status.pools[0]
             .progress
             .as_ref()
@@ -934,6 +967,16 @@ mod tests {
         assert_eq!(progress.remaining_buckets, 2);
     }
 
+    #[test]
+    fn test_rebalance_status_defaults_cleanup_warnings() {
+        let json = r#"{"id":"rebalance-1","pools":[{"id":0,"status":"Completed","used":0.5,"lastError":null,"progress":null}],"stoppedAt":null}"#;
+
+        let status: RebalanceStatus = serde_json::from_str(json).unwrap();
+
+        assert_eq!(status.pools[0].cleanup_warnings.count, 0);
+        assert_eq!(status.pools[0].cleanup_warnings.last_message, None);
+    }
+
     #[test]
     fn test_serialization() {
         let info = ClusterInfo {

crates/core/src/admin/mod.rs

@@ -11,8 +11,8 @@ pub use cluster::{
     BackendInfo, BackendType, BucketsInfo, ClusterInfo, DiskInfo, HealDriveInfo, HealDriveInfos,
     HealResultItem, HealScanMode, HealStartRequest, HealStatus, HealingDiskInfo, MemStats,
     ObjectsInfo, PoolDecommissionInfo, PoolErasureSetInfo, PoolStatus, PoolTarget,
-    RebalancePoolProgress, RebalancePoolStatus, RebalanceStartResult, RebalanceStatus, ServerInfo,
-    UsageInfo,
+    RebalanceCleanupWarnings, RebalancePoolProgress, RebalancePoolStatus, RebalanceStartResult,
+    RebalanceStatus, ServerInfo, UsageInfo,
 };
 pub use tier::{
     TierAliyun, TierAzure, TierConfig, TierCreds, TierGCS, TierHuaweicloud, TierMinIO, TierR2,

schemas/output_v2.json

@@ -435,13 +435,62 @@
         }
       }
     },
+    "rebalanceCleanupWarnings": {
+      "type": "object",
+      "required": [
+        "count",
+        "lastMsg",
+        "lastBucket",
+        "lastObject",
+        "lastAt"
+      ],
+      "properties": {
+        "count": {
+          "type": "integer",
+          "description": "Cleanup warning count"
+        },
+        "lastMsg": {
+          "type": [
+            "string",
+            "null"
+          ],
+          "description": "Last cleanup warning message"
+        },
+        "lastBucket": {
+          "type": [
+            "string",
+            "null"
+          ],
+          "description": "Bucket from the last cleanup warning"
+        },
+        "lastObject": {
+          "type": [
+            "string",
+            "null"
+          ],
+          "description": "Object from the last cleanup warning"
+        },
+        "lastAt": {
+          "oneOf": [
+            {
+              "$ref": "#/definitions/timestamp"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "description": "Timestamp of the last cleanup warning"
+        }
+      }
+    },
     "rebalancePoolStatus": {
       "type": "object",
       "required": [
         "id",
         "status",
         "used",
         "lastError",
+        "cleanupWarnings",
         "progress"
       ],
       "properties": {
@@ -464,6 +513,9 @@
           ],
           "description": "Last rebalance error for this pool"
         },
+        "cleanupWarnings": {
+          "$ref": "#/definitions/rebalanceCleanupWarnings"
+        },
         "progress": {
           "oneOf": [
             {